The China Lake is first used in S.O.G. when on the Jeep, clearing out entrenched Vietcong. It is also seen in the mission Crash Site when in the crashed plane fuselage, with Bowman questioning why the Russians would be using American weapons.
Unlocked at level 48. The China Lake has a 2 round capacity, and is pump-action. The pumping action is very slow, thus lowering the rate of fire as compared to a pump action shotgun.
The China Lake does 155-25 damage with a 7.5M blast radius. It drops about 17 damage per every meter meaning the lethal blast radius is about 3M as the damage would have dropped to 104.
With Scavenger, the starting ammo is doubled from 2 to 4 grenades.